I am always looking for new music to listen to, and Pandora has proved itself useful to this end. My musical preferences center on rock music, generally with metal and punk influences.
So far, I have two techniques for creating new stations. To create "Genre" stations, I seed all bands associated with a given genre according to Wikipedia articles. For these stations, I do not rate any songs. To create "Mix" stations, I seed all bands that I like within a heuristic genre distinction (for example, metal, punk, other rock). For these stations, I give songs the thumbs-up or down based on my preference. If anyone actually reads this and listens to my stations, I would love feedback to know if you think the Genre stations I have created accurately portray the given genres. My sense is that most stations often do, but some often don't (e.g., Mathcore).
Bands I like: The Black Dahlia Murder, The Absence, Protest the Hero, Trivium, Killswitch Engage, Atreyu, Avenged Sevenfold, All that Remains, Unearth, August Burns Red, As I lay Dying, System of a Down, Glassjaw, Thrice, Lagwagon, No Use for a Name, NOFX, Me First and the Gimme Gimmes, Rufio, Bracket, Strung Out, Billy Talent, My Chemical Romance, Weezer, f.o.c.u.s.